Slack today announced the availability of dark mode in its desktop app for Windows, Mac and Linux. This new dark mode will help users who work in the dark and users with visual impairments, migraines or other visual disorders. To switch to dark theme, go to Themes section under Preferences. You’ll get a preview of how everything will look and you can enable it if you like it. Slack is also adding new themes specifically for dark mode. The theme you select will reflect across platforms.
In the future, Slack will allow you to enable/disable dark mode based on OS theme using “sync with OS settings.”